Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly, idempotent, closed-world behavior, so the safety profile is covered. The description adds real value beyond that by disclosing the payload structure: sources, supersession links, three distinct dates, and the check with an optional source passage — details no annotation conveys. It stops short of stating behavior for a missing id or any limits on how much of the source passage is returned.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

A single front-loaded sentence with no filler, and the most useful facts (sources, links, dates) come first. The trailing clause about 'the check behind it: the method and, where kept, the passage' is dense and slightly awkward but still earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema and only one parameter, the description carries the return-value burden and does so reasonably by naming the fields returned. For a simple read tool that is close to complete; only error behavior and passage truncation are unaddressed.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

There is one parameter with full schema description coverage, including an example id format (clm_01J9X4N2), so the schema already does the work. The description only restates 'by id' and adds no meaning about id provenance, lookup scope, or failure on unknown ids. Baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific retrieval of a single claim by id and enumerates what comes back: sources, supersession links, three named dates, and the check (method plus optional source passage). That is far more specific than the title, and it reads clearly as a single-record lookup rather than a search. It does not explicitly distinguish itself from the generic 'fetch' sibling, which keeps it below a 5.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

'One claim by id' implies the precondition that the caller already holds a claim id, which is adequate implied usage. However, it never says how to obtain an id (e.g. via search) or when to prefer this over fetch/entity_state, and offers no exclusions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.